As I just finished laying track on my 1st layout and now test runnning engines, several engines (all brand new, ScaleTrains, Broadway) seem to run “jerky” on several areas of the track. The engine runs fine and then starts to run with a jerky motion in these areas. Not all engines are doing this. Like it’s not getting a constant flow of “power”. I clean the track, though track is new, but usually has no effect. Ideas, soultions, suggestions?
DCC system. HO scale. Peco code 83 flex track. Feeder wires every 3 feet or so.
This is all part of breaking the engines in as well. I heard you should run each new engine for a nour running forward and in reverse, and vering sppeds. That;s kida what I’ve been doing. But the process has uncovered some track issues with sone engines. Mostly delailing in a few turnouts.
P{retty easy to tell if it’s power or mechanical. Turn on the headlight. When the motion is jerky, are the headlights blinking on and off? If so, you have electrical pickup issues - dirty track, dirty wheels, dirty pickup wipers. Or if this is sectional track, loose rail joiners. If the headlight is nice and steady, but the loco moves in a jerky fashion, it’s likely a mechanical issue, although it could be a decoder setting issue as well - but that is unlikely to cause ALL locos to behave the same way.
If you have access to a suitable DC powerpack (borrow from someone?) you could replace the DCC power temporarily with DC and then test your locomotives in DC mode only. If they run fine that way you narrow the problem down to a DCC only issue. If all DCC locomotives run poorly in DCC but fine in DC then something isn’t right in your DCC setup.
Not all DC powerpacks are suitable for all brands of DCC locomotives so make sure the one you use is suitable before you plug it in.
I agree, if many locos are doing this, it is more likely to be an electrical problem. I have a few locos that do that, but they are older locos with limited power pickup on the wheels. The brand names of your locos suggest that it’s not a power pickup issue associated with your locomotives. Does the jerkiness occur at the same locations? Switches are the usual suspects, but it can also be dirty track, bad connections (are the rails soldered?), or uneven track.
The siderods are the moving parts on the outside of your steam engine’s big drive wheels. On a real engine, the steam goes to the cylinders on each side of the front of the engine, and the drive rods convert the front-to-back motion into a circular motion to drive the wheels forward or backwards. On a model steam engine, usually only one set of drive wheels are connected to the motor (on a 4-6-2 it’s probably the middle driver) and the siderods transmit the motion to the other drivers.
Sometimes on a new engine (or one that’s been handled improperly) a siderod can bend in a little bit. This can cause it to bind against the other rods or wheels. If you run the engine as slow as you can, and it hesitates once with each rotation of the drivers at the same spot, then that is likely the cause. Try to stop the engine where it binds and looks for something hitting something else.
BTW it’s “diesel”…in the Thomas the Tank Engine stories the steam engines sometimes call the diesels “diseasels” (play on “disease”).[(-D]
As Stix explained the side rods can get bent when the engine is picked up by them and can cause issues, so check to make sure they are straight.
Rapido made the side rods on the Hudson to scale and as a result they are getting bent a little easier than usual as they are thinner. Rapido has been warning about this issue.
It is very useful, for steamp operators, to have a cradle on which you can safely and securely invert and place the locomotive, and then fasten metal clamps to the tender’s wheels and run power that way. The tender provides power just as if the two were on powered rails, and you can dial in voltage/throttle setting and get the locomotive to start driving its drivers. Looking from overhead, eyes on the same planes as the side rods, main rod, and linkages, you will soon see how much slop is built into model trains, and whether or not one or more of those thin and soft metal rods has somehow been bent sufficiently to make swiping contact with another component, not just another rod.
With patient unbending, a wee bit at a time, the drives on either side of the steamer will function clear of each other’s rods and linkages, and you’ll be fine when you invert the locomotive and place it on the rails. Hopefully. If that doesn’t stop any jerking, it may be a cracked gear inside of the locomotive.
Based on the information we have received, I assume that the steamer is not the main problem. It would be useful to know which locos are suffering the most from this problem. 6 axle locos, for example, can have problems with some curves and switches.
Same thing here and this is my plan of action. Athearn 4 axle works excellently though.
Clean the loco wheels as they are probably tarnished from sitting on the store shelf for so long. Also see the thread on track cleaning or gleaming. New track usually also comes tarnished and has to be cleaned. Mine did and I buy Atlas code 100. I guess from people handling it in the hobby shop.
I saw a youtube video on code 83 Peco track on jerky operation on some of the switches, on the video it was the plastic on the frogs which caused the loco wheels to lose electrical pickup. What I found with switches in general on DCC is they have to be absolutely level you can’t have the diverging track declining already in slope before it leaves the switch as it will cause issues with the loco as it climbs that grade it might lift some of the wheels off of electrical contact. The other item with PECO specifically it said in the video is sometimes their frog insulation is too much or not enough…forget which but you have to watch for the tell tale short spark as the loco goes over the switch. I use code 100 Atlas.
Another issue I ran into but fixed was this was happening specifically in my auto reverse loop but then I found there was like a voltage control on the auto reverse circuit board
I had same issue but fixed with cork roadbed. Uneven turnouts #6 and above warp really easily if they are “bumpy”, barely noticeable to the naked eye, you have to look very carefully as the loco runs slowly over the section of the track for wheels lifting and the tell tale tiny DCC spark. 6 axles are prone to wheel lifting on sudden bumps or grades.
I would have to agree with CMStPnP pointing this out again.
Simon pointed out the six axel issues are common earlier and being that the OP says the six axle diesels are a problem on turnouts.
6 axle diesels can be quite finicky running over uneven or Twisted turnouts as they have a larger surface of contact to the rails. If so, the warp teeter-totter factor (if you will) is not doing you any good.
What’s been pointed out makes a lot of sense. I would take a piece of glass or plexiglass layed on the problem areas long enough to extend the approach and leave of the turnout and start checking things out. As easy as a thin shim or two may solve your problem[Y]
All my track is on cork roadbed. All my straight turnouts are #5’s and #6’s. One troubled turnout is on a down grade with the divergent track IS the main line. Derailing will occure on the down grade as it appears the wheel on the leading truck come up and over the point rail. Of course depending on the speed of the engine. Normal speeds of about 30-40 scaled MPH (and I’m just guessing) will be more prone to derail. Slower speeds usually have no problem. Engines running on the upgrade end never derail.
Engines runing past and thrugh the swtich yard seem to rock and bounch over all the turnouts. I will look much closer at leveling the turnouts.
BTW, all my turnouts are electrofrogs. And I have tried to file down some of that plastic insulation between the railes through the frogs. Seems sometimes this will raaise the wheels up as the run over these plastic areas.